Conventionally, a form that companies or individuals purchase servers and software at their own expense and utilize the same was mainstream, but cloud computing of utilizing servers and software via the Internet for reducing a TCO (Total Cost of Ownership) tends to spread.
As an example of cloud computing, in the Patent Literature 1, an invention of making a storage apparatus available via the Internet (hereinafter referred to as a cloud storage apparatus) is described.
Furthermore, in the Patent Literature 2, an invention related to a hierarchy storage system in which multiple storage apparatuses are combined is described.